A trio of Republicans wants some answers from Marriott on the breach of half a billion guest records going back over four years.

That came in a letter to Marriott president Arne Sorenson from Sen. John Thune of South Dakota, chairman of the Senate Commerce Committee; Roger Wicker, chairman of the Communications Subcommittee, and Jerry Moran, chairman of the Consumer Protection Subcommittee.

Marriott has apologized and has set up a Web site and call center to answer questions, emailed those impacted, and will provide a free online security monitoring service.

But the legislators still have a lot of questions about the breach they want answered. Those include when it discovered the breach, which dated back to 2014, how many credit card numbers were exposed (Marriott says they were encrypted, but isn't sure that the hackers didn't get the keys to unlock them), and a timeline of events, including relevant notifications or investigations.

They want those answers no later than 5 p.m. on Dec. 17.